Described below are a method for producing an electronic circuit and an electronic circuit.
In the production of electronic circuits there is a trend toward ever higher integration, that is to say toward accommodating more and more electronic components such as, for example, semiconductor chips on a carrier for the electronic circuit, for example a ceramic substrate, and thus toward producing ever more complex and more extensive electronic circuits. Although the yield in the production of an electronic circuit decreases as a result of the high integration and complexity, more cost-effective production overall is nevertheless achieved as a result.
In power electronic circuits, that is to say circuits having components appertaining to power electronics, one particular boundary condition for production is that a considerable amount of heat loss occurs in the power electronic circuit. This limits the possible packing density for the power electronic components, since the heat loss thereof has to be dissipated and the temperature of the power electronic components, primarily in the case of semiconductor components, must not exceed specific temperature limits. In this way, an increasing integration of more complex circuits on a substrate leads to circuits that are enlarged overall. Such circuits, however, in turn have their own disadvantages. Thus, the reliability of such an arrangement is reduced, especially in the case of cyclic thermal loading, since fatigue readily occurs at the interface between insulating carrier material and copper layer. Moreover, the high operating temperature of power electronic circuits leads to warpage of large-area substrates, which makes heat dissipation more difficult. Finally, the heat dissipation is also dependent on the best possible mechanical connection between a cooler and the substrate. The larger the substrate, the more stringent the requirements made of the cooler connected thereto, for example the planarity of the surface of the cooler.